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1.
Cell ; 186(21): 4546-4566.e27, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37769657

RESUMO

Neutrophils are abundant immune cells in the circulation and frequently infiltrate tumors in substantial numbers. However, their precise functions in different cancer types remain incompletely understood, including in the brain microenvironment. We therefore investigated neutrophils in tumor tissue of glioma and brain metastasis patients, with matched peripheral blood, and herein describe the first in-depth analysis of neutrophil phenotypes and functions in these tissues. Orthogonal profiling strategies in humans and mice revealed that brain tumor-associated neutrophils (TANs) differ significantly from blood neutrophils and have a prolonged lifespan and immune-suppressive and pro-angiogenic capacity. TANs exhibit a distinct inflammatory signature, driven by a combination of soluble inflammatory mediators including tumor necrosis factor alpha (TNF-ɑ) and Ceruloplasmin, which is more pronounced in TANs from brain metastasis versus glioma. Myeloid cells, including tumor-associated macrophages, emerge at the core of this network of pro-inflammatory mediators, supporting the concept of a critical myeloid niche regulating overall immune suppression in human brain tumors.

2.
Nat Immunol ; 24(10): 1645-1653, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37709986

RESUMO

Persistent exposure to antigen during chronic infection or cancer renders T cells dysfunctional. The molecular mechanisms regulating this state of exhaustion are thought to be common in infection and cancer, despite obvious differences in their microenvironments. Here we found that NFAT5, an NFAT family transcription factor that lacks an AP-1 docking site, was highly expressed in exhausted CD8+ T cells in the context of chronic infections and tumors but was selectively required in tumor-induced CD8+ T cell exhaustion. Overexpression of NFAT5 in CD8+ T cells reduced tumor control, while deletion of NFAT5 improved tumor control by promoting the accumulation of tumor-specific CD8+ T cells that had reduced expression of the exhaustion-associated proteins TOX and PD-1 and produced more cytokines, such as IFNÉ£ and TNF, than cells with wild-type levels of NFAT5, specifically in the precursor exhausted PD-1+TCF1+TIM-3-CD8+ T cell population. NFAT5 did not promote T cell exhaustion during chronic infection with clone 13 of lymphocytic choriomeningitis virus. Expression of NFAT5 was induced by TCR triggering, but its transcriptional activity was specific to the tumor microenvironment and required hyperosmolarity. Thus, NFAT5 promoted the exhaustion of CD8+ T cells in a tumor-selective fashion.


Assuntos
Coriomeningite Linfocítica , Neoplasias , Humanos , Fatores de Transcrição/metabolismo , Linfócitos T CD8-Positivos , Exaustão das Células T , Infecção Persistente , Microambiente Tumoral , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Vírus da Coriomeningite Linfocítica , Neoplasias/metabolismo
3.
Blood ; 139(16): 2483-2498, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35020836

RESUMO

NOTCH1 is a well-established lineage specifier for T cells and among the most frequently mutated genes throughout all subclasses of T cell acute lymphoblastic leukemia (T-ALL). How oncogenic NOTCH1 signaling launches a leukemia-prone chromatin landscape during T-ALL initiation is unknown. Here we demonstrate an essential role for the high-mobility-group transcription factor Tcf1 in orchestrating chromatin accessibility and topology, allowing aberrant Notch1 signaling to convey its oncogenic function. Although essential, Tcf1 is not sufficient to initiate leukemia. The formation of a leukemia-prone epigenetic landscape at the distal Notch1-regulated Myc enhancer, which is fundamental to this disease, is Tcf1-dependent and occurs within the earliest progenitor stage even before cells adopt a T lymphocyte or leukemic fate. Moreover, we discovered a unique evolutionarily conserved Tcf1-regulated enhancer element in the distal Myc-enhancer, which is important for the transition of preleukemic cells to full-blown disease.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Carcinogênese/genética , Linhagem Celular Tumoral , Cromatina/genética , Humanos , Oncogenes , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Receptor Notch1/genética
4.
Cerebellum ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38049694

RESUMO

Amyotrophic lateral sclerosis is a fatal neurodegenerative disorder that affects upper and lower motor neurons. SOD1 mutations are the second most commonly found in familial and sporadic cases. We describe a patient with a homozygous pathogenic mutation in SOD1 gene that presented with a progressive cerebellar ataxia and ultimately developed a complex phenotype of cerebellar ataxia and motor neuron disease. The linkage between the cerebellum and ALS is shortly discussed.

5.
Nephrol Dial Transplant ; 35(7): 1163-1170, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31006015

RESUMO

BACKGROUND: Zinc deficiency is commonly encountered in chronic kidney disease (CKD). The aims of this study were to assess whether zinc deficiency was related to increased renal excretion of zinc and to the progression of CKD. METHODS: Plasma and 24-h urinary zinc levels, urinary electrolytes and uromodulin were measured in 108 CKD patients and 81 individuals without CKD. Serum creatinine values were collected for 3 years to calculate the yearly change in estimated glomerular filtration rate (eGFR). Multivariable regression analysis was performed to assess the association between baseline zinc levels and yearly change in eGFR. RESULTS: CKD patients had lower circulating zinc levels and higher 24-h urinary zinc excretion than non-CKD participants (612.4 ± 425.9 versus 479.2 ± 293.0 µg/day; P = 0.02). Fractional excretion (FE) of zinc was higher and it significantly increased at more advanced CKD stages. Zinc FE was correlated negatively with 24-h urinary uromodulin excretion (r=-0.29; P < 0.01). Lower baseline plasma zinc levels were associated with a faster yearly decline of renal function in age, gender, diabetes and hypertension adjusted models, but this relationship was no longer significant when baseline eGFR or proteinuria were included. CONCLUSIONS: Zinc levels are lower in CKD, and not compensated by reduced renal zinc excretion. The inverse association between urinary zinc excretion and uromodulin possibly points to an impaired tubular activity, which could partly account for zinc imbalance in CKD. These data suggest that zinc status is associated with renal function decline, but further studies elucidating the underlying mechanisms and the potential role of zinc supplements in CKD are needed.


Assuntos
Insuficiência Renal Crônica/fisiopatologia , Zinco/sangue , Zinco/deficiência , Estudos de Casos e Controles , Creatinina/sangue , Progressão da Doença , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/urina , Uromodulina/urina
6.
Int J Mol Sci ; 21(18)2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32927821

RESUMO

Essential oils are complex mixtures of volatile compounds with diverse biological properties. Antimicrobial activity has been attributed to the essential oils as well as their capacity to prevent pathogenic microorganisms from forming biofilms. The search of compounds or methodologies with this capacity is of great importance due to the fact that the adherence of these pathogenic microorganisms to surfaces largely contributes to antibiotic resistance. Superparamagnetic iron oxide nanoparticles have been assayed for diverse biomedical applications due to their biocompatibility and low toxicity. Several methods have been developed in order to obtain functionalized magnetite nanoparticles with adequate size, shape, size distribution, surface, and magnetic properties for medical applications. Essential oils have been evaluated as modifiers of the surface magnetite nanoparticles for improving their stabilization but particularly to prevent the growth of microorganisms. This review aims to provide an overview on the current knowledge about the use of superparamagnetic iron oxide nanoparticles and essential oils on the prevention of microbial adherence and consequent biofilm formation with the goal of being applied on the surface of medical devices. Some limitations found in the studies are discussed.


Assuntos
Anti-Infecciosos , Biofilmes , Nanopartículas Magnéticas de Óxido de Ferro , Óleos Voláteis
7.
J Neuroeng Rehabil ; 16(1): 159, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31870399

RESUMO

BACKGROUND: Different types of sound cues have been used to adapt the human gait rhythm. We investigated whether young healthy volunteers followed subliminal metronome rhythm changes during gait. METHODS: Twenty-two healthy adults walked at constant speed on a treadmill following a metronome sound cue (period 566 msec). The metronome rhythm was then either increased or decreased, without informing the subjects, at 1 msec increments or decrements to reach, respectively, a low (596 msec) or a high frequency (536 msec) plateaus. After 30 steps at one of these isochronous conditions, the rhythm returned to the original period with decrements or increments of 1 msec. Motion data were recorded with an optical measurement system to determine footfall. The relative phase between sound cue (stimulus) and foot contact (response) were compared. RESULTS: Gait was entrained to the rhythmic auditory stimulus and subjects subconsciously adapted the step time and length to maintain treadmill speed, while following the rhythm changes. In most cases there was a lead error: the foot contact occurred before the sound cue. The mean error or the absolute mean relative phase increased during the isochronous high (536 msec) or low frequencies (596 msec). CONCLUSION: These results showed that the gait period is strongly "entrained" with the first metronome rhythm while subjects still followed metronome changes with larger error. This suggests two processes: one slow-adapting, supraspinal oscillator with persistence that predicts the foot contact to occur ahead of the stimulus, and a second fast process linked to sensory inputs that adapts to the mismatch between peripheral sensory input (foot contact) and supraspinal sensory input (auditory rhythm).


Assuntos
Estimulação Acústica , Marcha/fisiologia , Desempenho Psicomotor/fisiologia , Adaptação Fisiológica/fisiologia , Sinais (Psicologia) , Feminino , Voluntários Saudáveis , Humanos , Masculino , Caminhada/fisiologia , Adulto Jovem
8.
J Microencapsul ; 35(4): 392-405, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30112917

RESUMO

Pulmonary tuberculosis accounts for 80% of cases and the delivery of antitubercular drugs into the lungs allows targeting the infected organ and, possibly, reducing systemic drug toxicity. This work aimed at using fucoidan as matrix of inhalable microparticles that associate two first-line antitubercular drugs, for an application in pulmonary tuberculosis therapy. Fucoidan is composed of fucose and sulphated sugar residues, moieties described as being recognised by surface receptors of alveolar macrophages, which host mycobacteria. Inhalable fucoidan microparticles loaded with antitubercular drugs were successfully produced with high association efficiencies of either isoniazid (95%) or rifabutin (81%). The microparticles evidenced no cytotoxicity on lung epithelial cells (A549). However, rifabutin-loaded microparticles showed a certain degree of toxicity on macrophage-like cells (THP-1) at the highest tested concentration (1 mg/mL). Furthermore, microparticles showed favourable aerodynamic properties for deep lung delivery (MMAD 2.0-3.8 µm) and, thus, show potential for an application as inhalable tuberculosis therapy.


Assuntos
Antituberculosos/administração & dosagem , Portadores de Fármacos/química , Isoniazida/administração & dosagem , Polissacarídeos/química , Rifabutina/administração & dosagem , Células A549 , Administração por Inalação , Antituberculosos/farmacocinética , Linhagem Celular , Liberação Controlada de Fármacos , Humanos , Isoniazida/farmacocinética , Rifabutina/farmacocinética
9.
PLoS Genet ; 9(4): e1003457, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23593039

RESUMO

In animals, the population genomic literature is dominated by two taxa, namely mammals and drosophilids, in which fully sequenced, well-annotated genomes have been available for years. Data from other metazoan phyla are scarce, probably because the vast majority of living species still lack a closely related reference genome. Here we achieve de novo, reference-free population genomic analysis from wild samples in five non-model animal species, based on next-generation sequencing transcriptome data. We introduce a pipe-line for cDNA assembly, read mapping, SNP/genotype calling, and data cleaning, with specific focus on the issue of hidden paralogy detection. In two species for which a reference genome is available, similar results were obtained whether the reference was used or not, demonstrating the robustness of our de novo inferences. The population genomic profile of a hare, a turtle, an oyster, a tunicate, and a termite were found to be intermediate between those of human and Drosophila, indicating that the discordant genomic diversity patterns that have been reported between these two species do not reflect a generalized vertebrate versus invertebrate gap. The genomic average diversity was generally higher in invertebrates than in vertebrates (with the notable exception of termite), in agreement with the notion that population size tends to be larger in the former than in the latter. The non-synonymous to synonymous ratio, however, did not differ significantly between vertebrates and invertebrates, even though it was negatively correlated with genetic diversity within each of the two groups. This study opens promising perspective regarding genome-wide population analyses of non-model organisms and the influence of population size on non-synonymous versus synonymous diversity.


Assuntos
Drosophila/genética , Genoma Humano , Metagenômica , Transcriptoma/genética , Animais , Sequência de Bases , Genótipo , Lebres/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Invertebrados/genética , Isópteros/genética , Ostreidae/genética , Polimorfismo de Nucleotídeo Único , Tartarugas/genética , Urocordados/genética , Vertebrados/genética
10.
Molecules ; 21(6)2016 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-27240337

RESUMO

Tuberculosis remains a major global health problem and alternative therapeutic approaches are needed. Considering the high prevalence of lung tuberculosis (80% of cases), the pulmonary delivery of antitubercular drugs in a carrier system capable of reaching the alveoli, being recognised and phagocytosed by alveolar macrophages (mycobacterium hosts), would be a significant improvement to current oral drug regimens. Locust bean gum (LBG) is a polysaccharide composed of galactose and mannose residues, which may favour specific recognition by macrophages and potentiate phagocytosis. LBG microparticles produced by spray-drying are reported herein for the first time, incorporating either isoniazid or rifabutin, first-line antitubercular drugs (association efficiencies >82%). Microparticles have adequate theoretical properties for deep lung delivery (aerodynamic diameters between 1.15 and 1.67 µm). The cytotoxic evaluation in lung epithelial cells (A549 cells) and macrophages (THP-1 cells) revealed a toxic effect from rifabutin-loaded microparticles at the highest concentrations, but we may consider that these were very high comparing with in vivo conditions. LBG microparticles further evidenced strong ability to be captured by macrophages (percentage of phagocytosis >94%). Overall, the obtained data indicated the potential of the proposed system for tuberculosis therapy.


Assuntos
Antituberculosos/administração & dosagem , Galactanos/administração & dosagem , Macrófagos Alveolares/efeitos dos fármacos , Mananas/administração & dosagem , Gomas Vegetais/administração & dosagem , Tuberculose/tratamento farmacológico , Células A549 , Administração por Inalação , Antituberculosos/efeitos adversos , Antituberculosos/química , Sistemas de Liberação de Medicamentos , Galactanos/efeitos adversos , Galactanos/química , Humanos , Macrófagos Alveolares/patologia , Mananas/efeitos adversos , Mananas/química , Microesferas , Mycobacterium tuberculosis/efeitos dos fármacos , Tamanho da Partícula , Fagocitose/efeitos dos fármacos , Gomas Vegetais/efeitos adversos , Gomas Vegetais/química
11.
Molecules ; 21(9)2016 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-27618006

RESUMO

Biofilm bacteria are more resistant to antibiotics than planktonic cells. Propolis possesses antimicrobial activity. Generally, nanoparticles containing heavy metals possess antimicrobial and antibiofilm properties. In this study, the ability of adherence of Methicillin Resistant Strains of Staphylococcus aureus (MRSA) to catheters treated with magnetite nanoparticles (MNPs), produced by three methods and functionalized with oleic acid and a hydro-alcoholic extract of propolis from Morocco, was evaluated. The chemical composition of propolis was established by gas chromatography mass spectrometry (GC-MS), and the fabricated nanostructures characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Mossbauer spectroscopy and Fourrier transform infrared spectroscopy (FTIR). The capacity for impairing biofilm formation was dependent on the strain, as well as on the mode of production of MNPs. The co-precipitation method of MNPs fabrication using Fe(3+) and Na2SO3 solution and functionalized with oleic acid and propolis was the most effective in the impairment of adherence of all MRSA strains to catheters (p < 0.001). The adherence of the strain MRSA16 was also significantly lower (p < 0.001) when the catheters were treated with the hybrid MNPs with oleic acid produced by a hydrothermal method. The anti-MRSA observed can be attributed to the presence of benzyl caffeate, pinocembrin, galangin, and isocupressic acid in propolis extract, along with MNPs. However, for MRSA16, the impairment of its adherence on catheters may only be attributed to the hybrid MNPs with oleic acid, since very small amount, if any at all of propolis compounds were added to the MNPs.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Biofilmes , Nanopartículas de Magnetita/química , Staphylococcus aureus Resistente à Meticilina/fisiologia , Própole , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Marrocos , Própole/química , Própole/farmacologia
12.
Mol Biol Evol ; 30(6): 1292-301, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23412912

RESUMO

It is currently unclear whether the amino acid substitutions that occur during protein evolution are primarily driven by adaptation, or reflect the random accumulation of neutral changes. When estimated from genomic data, the proportion of adaptive amino acid substitutions, called α, was found to vary greatly across species, from nearly zero in humans to above 0.5 in Drosophila. These variations have been interpreted as reflecting differences in effective population size, adaptation being supposedly more efficient in large populations. Here, we investigate the influence of effective population size and other biological parameters on the rate of adaptive evolution by simulating the evolution of a coding sequence under Fisher's geometric formalism. We explicitly model recurrent environmental changes and the subsequent adaptive walks, followed by periods of stasis during which purifying selection dominates. We show that, under a variety of conditions, the effective population size has only a moderate influence on α, and an even weaker influence on the per generation rate of selective sweeps, modifying the prevalent view in current literature. The rate of environmental change and, interestingly, the dimensionality of the phenotypic space (organismal complexity) affect the adaptive rate more deeply than does the effective population size. We discuss the reasons why verbal arguments have been misleading on that subject and revisit the empirical evidence. Our results question the relevance of the "α" parameter as an indicator of the efficiency of molecular adaptation.


Assuntos
Adaptação Biológica/genética , Evolução Molecular , Interação Gene-Ambiente , Modelos Genéticos , Substituição de Aminoácidos , Animais , Simulação por Computador , Drosophila/genética , Meio Ambiente , Genes , Genoma , Humanos , Proteínas/química , Proteínas/genética
13.
Toxins (Basel) ; 16(4)2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38668625

RESUMO

Okadaic acid (OA) is one of the most potent marine biotoxins, causing diarrheal shellfish poisoning (DSP). The proliferation of microalgae that produce OA and its analogues is frequent, threatening human health and socioeconomic development. Several methods have been tested to remove this biotoxin from aquatic systems, yet none has proven enough efficacy to solve the problem. In this work, we synthesized and characterized low-cost composites and tested their efficacy for OA adsorption in saltwater. For the synthesis of the composites, the following starting materials were considered: chitosan of low and medium molecular weight (CH-LW and CH-MW, respectively), activated carbon (AC), and montmorillonite (MMT). Characterization by vibrational spectroscopy (FTIR), X-ray diffraction (XRD), and microscopy revealed differences in the mode of interaction of CH-LW and CH-MW with AC and MMT, suggesting that the interaction of CH-MW with MMT has mainly occurred on the surface of the clay particles and no sufficient intercalation of CH-MW into the MMT interlayers took place. Among the composites tested (CH-LW/AC, CH-MW/AC, CH-MW/AC/MMT, and CH-MW/MMT), CH-MW/MMT was the one that revealed lower OA adsorption efficiency, given the findings evidenced by the structural characterization. On the contrary, the CH-MW/AC composite revealed the highest average percentage of OA adsorption (53 ± 11%). Although preliminary, the results obtained in this work open up good perspectives for the use of this type of composite material as an adsorbent in the removal of OA from marine environments.


Assuntos
Bentonita , Quitosana , Ácido Okadáico , Adsorção , Quitosana/química , Ácido Okadáico/química , Bentonita/química , Carvão Vegetal/química , Toxinas Marinhas/química , Intoxicação por Frutos do Mar/prevenção & controle
14.
Trends Mol Med ; 30(9): 804-808, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38839514

RESUMO

Polyglutamine (polyQ) disorders are monogenic neurodegenerative disorders. Currently, no therapies are available for this complex group of disorders. Here, we aim to provide an overview of recent promising preclinical studies and the ongoing clinical trials focusing on molecular therapies for polyQ disorders.


Assuntos
Ensaios Clínicos como Assunto , Doenças Neurodegenerativas , Peptídeos , Humanos , Peptídeos/uso terapêutico , Animais , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/terapia , Doenças Neurodegenerativas/metabolismo , Terapia de Alvo Molecular/métodos
15.
Cancer Cell ; 42(3): 378-395.e10, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38242126

RESUMO

Brain metastasis (BrM) is a common malignancy, predominantly originating from lung, melanoma, and breast cancers. The vasculature is a key component of the BrM tumor microenvironment with critical roles in regulating metastatic seeding and progression. However, the heterogeneity of the major BrM vascular components, namely endothelial and mural cells, is still poorly understood. We perform single-cell and bulk RNA-sequencing of sorted vascular cell types and detect multiple subtypes enriched specifically in BrM compared to non-tumor brain, including previously unrecognized immune regulatory subtypes. We integrate the human data with mouse models, creating a platform to interrogate vascular targets for the treatment of BrM. We find that the CD276 immune checkpoint molecule is significantly upregulated in the BrM vasculature, and anti-CD276 blocking antibodies prolonged survival in preclinical trials. This study provides important insights into the complex interactions between the vasculature, immune cells, and cancer cells, with translational relevance for designing therapeutic interventions.


Assuntos
Neoplasias Encefálicas , Neoplasias da Mama , Melanoma , Camundongos , Animais , Humanos , Feminino , Neoplasias Encefálicas/patologia , Encéfalo/metabolismo , Neoplasias da Mama/patologia , Fatores de Transcrição/metabolismo , Microambiente Tumoral , Antígenos B7
16.
Cancer Cell ; 42(9): 1507-1527.e11, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39255775

RESUMO

Glioblastoma recurrence is currently inevitable despite extensive standard-of-care treatment. In preclinical studies, an alternative strategy of targeting tumor-associated macrophages and microglia through CSF-1R inhibition was previously found to regress established tumors and significantly increase overall survival. However, recurrences developed in ∼50% of mice in long-term studies, which were consistently associated with fibrotic scars. This fibrotic response is observed following multiple anti-glioma therapies in different preclinical models herein and in patient recurrence samples. Multi-omics analyses of the post-treatment tumor microenvironment identified fibrotic areas as pro-tumor survival niches that encapsulated surviving glioma cells, promoted dormancy, and inhibited immune surveillance. The fibrotic treatment response was mediated by perivascular-derived fibroblast-like cells via activation by transforming growth factor ß (TGF-ß) signaling and neuroinflammation. Concordantly, combinatorial inhibition of these pathways inhibited treatment-associated fibrosis, and significantly improved survival in preclinical trials of anti-colony-stimulating factor-1 receptor (CSF-1R) therapy.


Assuntos
Neoplasias Encefálicas , Fibrose , Glioblastoma , Recidiva Local de Neoplasia , Microambiente Tumoral , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Animais , Humanos , Camundongos , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Microambiente Tumoral/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Receptor de Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Fator de Crescimento Transformador beta/metabolismo
17.
J Environ Manage ; 128: 226-32, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23747373

RESUMO

This work describes the synthesis of CuS powders in high yield and via an environmentally friendly and straightforward process, under ambient conditions (temperature and pressure), by adding to aqueous copper (II) a nutrient solution containing biologically generated sulfide from sulfate-reducing bacteria (SRB). The powders obtained were composed of CuS (covellite) nanoparticles (NPs) exhibiting a spheroid morphology (<5 nm). The relevance of this method to obtain CuS supported solid substrates has been demonstrated by performing the synthesis in the presence of TiO2 and SiO2 submicron particles. We further extended the work carried out, which substantiates the potential of using biogenic sulfide for the production of covellite nanocrystals and composites, using the effluent of a bioremediation column. Hence, such process results in the synthesis of added value products obtained from metal rich effluents, such as metallurgical and industrial ones, or Acid Mine Drainage (AMD), when associated with bioremediation processes.


Assuntos
Biodegradação Ambiental , Cobre/química , Nanopartículas/química , Cobre/isolamento & purificação , Desulfovibrio desulfuricans/metabolismo , Microscopia Eletrônica de Varredura , Nanopartículas/ultraestrutura , Dióxido de Silício , Titânio , Difração de Raios X
18.
Case Rep Psychiatry ; 2023: 7960227, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36969133

RESUMO

Postictal psychosis (PIP) is one of the most common types of psychosis in epileptic patients. By virtue of the paucity of research on PIP, its pathophysiology remains not completely understood. Our case report describes a clinical picture of PIP, characterized by pleomorphic features, with neither Schneider's first-rank symptoms nor negative symptoms of schizophrenia, in a longstanding epileptic female patient with a history of nonadherence to antiepileptic treatment and poorly controlled seizures. Additionally, she had previous cognitive impairment and encephalomalacia in the right parietooccipital region as a sequela of a moderate-to-severe traumatic brain injury known to precede the emergence of the epilepsy. In light of our findings, we critically reviewed the current literature on postictal psychoses providing insight into its neurobiological underpinnings.

19.
Food Chem ; 402: 134463, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36303366

RESUMO

Se in the form of sodium selenite was microencapsulated by spray - drying and added to a food matrix (yogurt) to study the potential improvement of its bioaccessibility. Yogurt samples were also supplemented with Se in free salt form. Se-loaded microparticles were successfully prepared by spray-drying with production yields above 70%. The supplementation of yogurt with Se in the form of free sodium selenite had a low effect on improving the bioaccessibility of this micronutrient (1%). In turn, Se microencapsulation with mannitol or mannitol/gastro-resistant polymer (Eudragit®) had a strong impact on bioaccessibility results. After the gastric phase, Se bioaccessibility reached values of 21 and 40% for the microencapsulated formulations, respectively. This percentage rose to 55% at the end of intestinal phase, showing no differences between both formulations. Our results show the relevance of microencapsulation as an effective tool to improve the bioaccessibility of micronutrients when they are used in food supplementation.


Assuntos
Selênio , Selenito de Sódio , Composição de Medicamentos/métodos , Suplementos Nutricionais , Micronutrientes , Manitol
20.
Front Immunol ; 14: 1335207, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38304252

RESUMO

The transforming growth factor-ß (TGF-ß) family member activin A (hereafter Activin-A) is overexpressed in many cancer types, often correlating with cancer-associated cachexia and poor prognosis. Activin-A secretion by melanoma cells indirectly impedes CD8+ T cell-mediated anti-tumor immunity and promotes resistance to immunotherapies, even though Activin-A can be proinflammatory in other contexts. To identify underlying mechanisms, we here analyzed the effect of Activin-A on syngeneic grafts of Braf mutant YUMM3.3 mouse melanoma cells and on their microenvironment using single-cell RNA sequencing. We found that the Activin-A-induced immune evasion was accompanied by a proinflammatory interferon signature across multiple cell types, and that the associated increase in tumor growth depended at least in part on pernicious STING activity within the melanoma cells. Besides corroborating a role for proinflammatory signals in facilitating immune evasion, our results suggest that STING holds considerable potential as a therapeutic target to mitigate tumor-promoting Activin-A signaling at least in melanoma.


Assuntos
Ativinas , Melanoma , Fator de Crescimento Transformador beta , Evasão Tumoral , Animais , Camundongos , Ativinas/metabolismo , Melanoma/imunologia , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Microambiente Tumoral
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